1. Field of the Invention
The present invention relates to imaging apparatus and method that are capable of providing smooth imaging when playing images back in slow playback mode.
2. Description of the Related Art
In current video cameras, a solid-state imaging section (CCD image sensor) that is formed by a plurality of solid-state imaging elements, is used as an imaging means that is smaller and lighter than an imaging tube and which can be produced at a low cost. The construction of a general type of CCD image sensor is shown in FIG. 1A.
FIG. 1A shows a video camera 70 of the past, which has a CCD image sensor 71, which performs imaging of the subject that is shown in the drawing, a correlated double sampling/automatic gain controller (CDS/AGC) 72, which eliminates noise components from the signal from the CCD image sensor 71, an analog-to-digital converter (ADC) 73, which converts the video signal from the CDS/AGC 72 to a digital signal, and a digital signal processor (DSP) 74, which converts the output from the ADC 73.
The video camera 70 further has a memory 77 for temporary storage of a video signal from the DSP 74, a video tape recorder (VTR) 76, which records onto and plays back from a video tape a video signal from the DSP 74, and a memory controller (FMC) 75, which performs control of readout from the memory 77.
In the video camera 70, the video signal from the CCD image sensor 71 is read out, via the CDS/AGC 72, ADC 73, DSP 74, and FMC 75, for each first field and second field, this video signal being recorded by the VTR 76.
That is, in the CCD image sensor 71, electrical charges of the photoelectric conversion element are read out one at a time within one field period, and the images of the first field and the second field are synthesized therefrom, thereby forming the single frame image, as shown in FIG. 1B, this being recorded onto a video tape via the VTR 76.
In order to play back an image that is recorded onto the video tape, in addition to supplying the output from the VTR 76 to the memory controller FMC 75, as shown in FIGS. 1C and 1D, while storing this output in the memory 77, it is output, via an output terminal 78, to an external monitoring device, such as an electronic viewfinder, a compact LCD monitor, or a TV receiver.
In the particular case of video cameras of the past, when playing the images recorded on a video tape in slow playback mode, for example, at 1/10 the normal speed, by playing back the first field image 10 times, and then playing back the second field image 10 times, or by repeating the image of one frame 10 times, or the like, the image of one frame was repeated over a period of 10 frames.
With the above-noted video camera of the past, however, as described above, because slow playback is achieved by displaying one and the same image over a plurality of field periods, it was difficult to improve the dynamic image resolution during slow playback.